US 2013/0012999 discloses an orthopedic implant kit comprising several items, in particular a pedicle screw fixed to a mounting tube made of two half-shells which can be easily disassembled.
Pedicle screws of the prior art can be divided in two main groups:                Mono-axial screws: The direction of the screw main axis is fixed with respect the screw head;        Poly-axial screws: The orientation of the screw main axis can be freely modified with respect to the screw head.        
When implanting a pedicle screw into a bone several steps are needed. For almost each of those steps a dedicated instrument is used.